Definition of identifiers:
(n) :
Something that identifies or uniquely points to something or someone else.
(n) :
(programming, operating systems) A formal name used in source code to refer to a variable, function, procedure, package, etc. or in an operating system to refer to a process, user, group, etc.
(n) :
(HTML) A code that distinguishes a particular element from all other elements in a document.
(n) :
Someone who identifies; a person who establishes the identity of someone or something.
(n) :
One who identifies as a particular type or role; one who says and believes that they are a certain thing.
(n) :
A guidebook that helps determine the specific class of an object (such as a mushroom, herb, fish, bird, drug, or mineral), or its individual identity (such as that of a star).